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Discussion Starter #1
I replaced the ball stud on the back of the shift lever but the threads on the shift lever are worn and I'm afraid to tighten them up firmly. They need to be repaired. I've never helicoiled a thread before but it doesn't look overly difficult. Are there any tricks or advice you can offer me. I don't have any helicoil tools at this point. Should I be looking for a machine shop to do this for me?
Thanks for the help.
Bob
 

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Hi bob

Helicoils are quite easy to do mate as the kit has the correct drill bit for the coil and also the tap to cut the thread that the coil uses. If you do know someone in a automotive shop or engineering shop that will help moreso as the kits alone are not cheap to buy but to use a single coil is not dear on its own
 

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This product works very well and would be ideal in the application you have. Available at your local auto part dealer.

Permatex® Stripped Thread Repair

Makes reliable thread repairs without drills, taps, tools or inserts. Restores worn, stripped or damaged threads and eliminates future corrosion, galling, seizing and rust. Effective up to 128 ft. lbs. of torque and between -65°F to 300°F (-54°C to 149°C). Repairs most metal-to-metal fasteners up to SAE grade 5 English and 8.8 metric (coarse and fine).

Suggested Applications:
Intake manifold bracket fastener threads, timing chain cover bolt threads, valve cover bolt threads, water pump bolt threads
 

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Do you know what the thread size is? I have a set of Snap-On thread restorers that have worked well for me in the past. I could send the right size to you if I have it. Works just like a tap only restores the existing threads.
 

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Discussion Starter #7
Thanks for all the suggestions. I've found a local machine shop that will do the job for me. The helicoil kit is $120 and I'm not likely to use it much. I tend to shy away from the quick fix thread repair stuff. This is a critical application and needs to be done 100%.

BTW, the issue with the ball stud was that the threaded brass insert bushing was worn badly due to loosening of the ball stud. This eventually caused the failure of the stud and damage to the threads. I was fairly good at checking and lubricating the linkage so it must've happended pretty quickly.

Thanks,
Bob
 

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I had to do the exact same job, and the helicoil is still working after three years. Those darn kits are expensive though, around $35 for a helicoil kit. I've done two of these now (one for the exhaust manifold), and should have bought the big kit that has several sizes of threads. This would have been cheaper.
 

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Wow $120

As I said you dont need to buy a kit unless you do a lot of machine work. You can however just get the replacement thread coil cheaply enough usually in a pack of 5 from a bolt/fastener trade hardware supply store. Most engine workshops will have the kits as they use them regularly and if you know someone they may let you borrow the drill bit tap and coil installation tool. The helicoil or similar usually end up being somewhat stronger than the original thread and most times the thread damaged has exceeded its stress limit and will fail with touch up type pastes repair bonds etc even though Permatex is a very good bonding agent but again it still has its limitations. Make sure though that if you are going to use a helicoil to get stainless ones if they are going into aluminium as it won't corrode like steel coils do and also cause electrolysis between the metals
 
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